Fuse.



P. W. YOUNG.

FUSE. APPLIOATION FILED KAB.14. 1907.

PATENTED NOV. 26, 1907.

(June/misc alto-Lump PATENTED NOV. 26, 1907.

F. W. YOUNG.

FUSE.

APPLICATION mum In. 14. 1907,

2 SHEETS-BHEET 2.

I 1 I 1 f l (A Illl Q vi bneowo affozucl a FREDERICK WM. YOUNG, OF EAST ORANGE, NEW JERSEY.

FUSE.

Specification of Letters Patent.

Patented Nov. 26, 1907.

Application filed March 14. 1907. Serial No. 362.347

T 0 all whomit may concern:

Be it known that I, FREDERICK WILLIAM YOUNG, a citizen of the United States, residingat East Orange, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Fuses; and I do declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to fuses for electrical circuits.

The principal object of the invention is to provide a fuse which will open the circuit in any system having either a high or low voltage without subjecting the internal parts thereof to any flame, the are being extinguished as soon as formed, by the use of which high tension systems may be brought into safer limits.

Another object of the invention is to produce a cheaply constructed fuse which may be made much smaller than the fuse now in ordinary use.

In the accompanying drawings :Figure 1 represents a vertical section of a fuse embodying one form of the invention; Fig. 2 represents a transverse section, taken on the line 22 of Fig. 1; Fig. 3 represents a side elevation of a compound fuse element before the ends are soldered together; Fig. 4 represents a transverse section of the fuse member before it is compressed; Fig. 5 represents a vertical section of a modified form of fuse embodying this invention; Fig. 6 represents a transverse section thereof, taken on line 6-6 of Fig. 5; Fig. 7 represents a vertical section of another modification; Fig. 7 represents a similar view of another modification. Fig. 8 represents a vertical section of the upper half of another modified form of fuse embodying this invention; and Fig. 9 represents a transverse section thereof, taken on line 99 of Fig. 8.

In the embodiment illustrated in Figs. 1 to 4, a fuse is shown comprising a retaining tube or casing 1 of porcelain, glass or any other suitable insulating material and having-at its ends metal caps 2 and 3 to which the ends of the fuse element 4 are connected. This casing is preferably filled with oil, as 5, which is preferably poured into the casing while hot until the chamber therein is filled, so that when the oil becomes cold a vacuum, as 6, is formed in said chamber which is very desirable when the fuse blows on short circuit. A vacuum being maintained above the oil level, then upon the blowing of the fuse, the force from within may be balanced by the atmospheric pressure from without. When a fuse blows on short circuits, considerable energy is liberated and the oil in the chamber of the tube 1 is greatly disturbed and immediately washes over the are and smothers it without giving it a chance to establish itself, break the tube and continue between the terminals.

The fuse member 10 is preferably composed of a plurality of thin metal elements 11 separated from each other by asbestos 12 or other suitable insulating material. The ends of said elements 11 project beyond the asbestos insulation 12 and are soldered together and to the wires 13 and 14 at the opposite ends of the tube 1. This fuse member 10 as shown in Figs. 1 to 4, is made from a sheet of asbestos bent or folded into zig-zag form, as shown in Fig. 4, with a thin strip of metal, as 12, of low fusing point placed in each fold of the asbestos to insulate them from each other and the asbestos is then pressed into position and secured in any suitable manner.

When a fuse constructed as above described ruptures, the are formed by such rupture is split up into many parts and each part is separated by non-combustible, nonconducting wall. This splitting of the are greatly diminishes its intensity, it being in fact smothered by the asbestos as soon as it is established and it cannot reach out since the metal parts are inclosed. It is found in practice that the combustible thread which is preferably used to secure the asbestos and metal fuse elements together is not even burned after the rupture of the fuse, showing that there is no harmful are formed. An arc of so little intensity prevents dangerous loads on the generator system, such as meters, circuit breakers, generators and prime movers.

The caps 2 and 3 may be of brass or copper and may be fastened to the tube 1 by plaster of paris, as 7, lead or other suitable substance not affected by oil.

The disturbance of the oil caused by the current rupture, manifests itself as pressure against the tube and caps and unless they are strong enough to stand it they will burst. To provide for such contingencies vent holes, as 16, are formed in the cap and these holes are plugged to prevent the oil from evaporating. When a fuse blows out and the pressure is high these plugs will fly out and the strain is removed. Very thin metal disks may also be soldered over these vent holes, as shown in Fig. 1. This will keep the tube air-tight yet render it safe in case of high pressure from within, or the entire upper eap may be covered with a single safety disk which will ru ture very easily when the pressure from witliin is high. One mill sheet copper is a very desirable material to use for this purpose. The above structure applies to a tube filled nearly to the top with oil and having no vacuum; the tube, however, may be so constructed that the pressure from without will offset the pressure from within and thus form a balance, which will keep the tubes and caps safe against breaking. Any of these structures may be employed with a vacuum in combination and thus still further improve the action of the fuse and render it a safe and positive acting instrument.

The fuse constructed as described will work on moderately high voltage circuits when simply inelosedin a shell but to further improve the conditions and makeit operative for very high voltages, such as one, ten,

twenty and thirty thousand volts etc., the fuse ispreferably hermetically sealed in the,

oil filled casing, one capable of holding oil and to insulate the poles at either end.

In the forms shown in Figs. 5 and 6 the metal element 11 is rolled in an asbestos sheet 12 and the cap is there shown provided with two small safety disks 17 and 18.

In the form shown in Fig. 7, the tube 20 has screw-threads 21 at one end with a gasket 22 of cork or other suitable material disposed between the endthereof and the ca 23 and at its other end with a threaded col ar 24 secured thereto by plaster-ofaris anda metal cap 26 is secured to the col ar 24 with a gasket 27 arranged between the ends of the tube and said cap 26.

In the forms shown in Figs. 8 and 9, the cap 30 is'sprun over the tube 31 with a gasket 32 disposed. between the end of the tube and the cap in much the same manner as caps are fastened on bodies. The fuse element shown in these fi ures consists of metal I I elements 11" disposed etween blocks of asbestos '12 and then highly compressed to fasten them to ether.

'In order to irect the strains set up by theblowing of the fuse in definite drections, the

fuse element is surroundedby an inner tube 35. This will, when the fuse blows, protect the central warts of the outer tube from the severe momentary strain and at the same time cause this strain to act upon the end caps on which it is intended the pressure should act, they being provided with relief safety devices.

Having thus described my invention, what I claim as new and des re to secure by Letters-Patent, 1s:

1. A fuse for electric circuits comprisinf a retaining tube having a fuse member dis-v posed therein and composed of a sheet of insulating material folded in zigzag form and having thin metal elements folds thereof.

3. A fuse for electric circuits comprising an air-tight retaining tube partly filled with oil and having a vacuum at one end and a fuse member arranged therein and immersed in the oil.

4. A fuse for electric circuits comprising an air-tight retaining tube having a fuse mem-.' ber disposed therein and composed of thin metal elements arranged between insulatin material, said tube being filled with oil around said fuse member and having means for sealing its ends.

5. A fuse for electric circuits comprisin a retaining tube having a fuse member isarranged in the .posed therein and composed of a plurality of metal elements insulated one from the other andan inner tube closely hugging the middle portion of said member.

6. A fuse for electric circuits comprising a retaining tube filled with oil and having a fuse member arranged therein and immersed in the oil, and an inner tube closely surrounding said fuse member. I

7. A fuse for electric circuits retaining tube filled with oil and having a fuse member arranged therein and immersed in oil, and an inner strain directing tube closely surrounding the middle portion of said fuse member.

. 8. A fuse for electric circuits comprisin a I 1 110 retaining tube having a fuse member isposed therein, an inner strain directing tube closely surrounding said fuse member, and thin metal closures for the retaining tube lightly secured thereto.

In testimony. whereof I have hereunto set my hand in presence of two subscribing witnesses.

FREDERICK YOUNG.

. Witnesses:

HENRY J. FU'LLER, HOWARD M. .GAssMAN,

comprising a 

